Thermal mass flowmeters

Thermal meters:
For direct mass measurement of industrial gases, compressed air, and aqueous fluids

What is a Thermal Mass Flow Meter?

A thermal mass flow meter is a precision instrument,

that measures gas mass flow and is used in various industries,

with a wide range of applications.

Sino-Instrument’s thermal mass flowmeters,

made in China,

are suitable for all industrial and test rig applications,

that demand quick and precise gas measurement.

The flowmeters indicate the mass flow or normalized volume flow of gases,

without any additional pressure and temperature compensation.

They have impressively high accuracy,

short response time and a very wide flow range with virtually no loss of accuracy even at the lowest flow rates.

Whenever high turn down or low-pressure losses,

are important in gas metering applications,

in any industry,

thermal mass flowmeters offer a real alternative to traditional measuring techniques,

whether for process control, consumption and supply monitoring,

detecting leaks or monitoring distribution networks.

Using insertion versions,

it is also possible to measure gas flows in very large pipelines or in rectangular ducts.

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Features of SI-RSL Thermal Mass Flow Meter :

  • Patented platinum RTD sensor;
  • Medium temperature self-compensation;
  • High linearity, high repeatability, high precision;
  • The range ratio is 1000:1;
  • Resolution 0.01m/s;
  • Straight pipe requirements are not high 1-2D;
  • The maximum temperature can reach +450 °C;
  • Online dynamic correction of current/voltage output;
  • Pressure:0-16MPa

Parameters of SI-RSL Thermal Mass Flow Meter:

Measuring range: 0-120 Nm / s (20 ° C, 101.33 KPa)
Accuracy: ±1% of reading ±0.5% of the full scale
Range ratio: usually 100:1 (depending on the calibration flow range)
Pipe diameter range: 10mm-6000mm
Applications: Suitable for all types of single or mixed gases. Dust, sand, moisture, various corrosive gases
Ambient temperature range: -40°C~+85°C (no display); -30°C~+70°C (shown); humidity less than 90RH
Medium temperature range: -40°C~+100°C; -40°C~+200°C; -40°C~+350°C
Sensor Diameter: 3, 2.5
Plug-in sensor exploration diameter: 19 (standard), 16, 12
Sensor material: 304, 316 stainless steel, Hastelloy, titanium
Probe material (protective sleeve): 304, 316 stainless steel, Hastelloy
Bidirectional measurement of media flow
Analog output: Flow: 4-20mADC, temperature: 4-20mADC, load 1000
Cumulative pulse output
Type 12-segment nonlinear correction with built-in 10-band nonlinear repair
Communication: serial output RS232/RS485
Power supply: 24VDC/600mA; 220VAC/13W; 110VAC/15W
Alarm: 1-2 relay output, 5A/220V, 5A/30VDC, typesetting
Large-screen LCD display: seven-bit instantaneous flow, eight-digit cumulative flow
Process pressure: 1.6MPa (20MPa)
Installation process: plug-in type (sleeve, ferrule + ball valve, flange connection),
pipe type (flange, threaded connection)
Explosion-proof grade Exd II CT6
Protection level: IP65

SI-RSL Thermal mass flowmeters
SI-RSL Thermal mass flowmeters

Thermal flow measuring principle

This measuring principle is based on the fact,

that heat is drawn from a heated body when a fluid flows past.

Thermal flow measuring principle

The thermal mass flow meter is a flow meter based on the principle of thermal diffusion.

That is when the fluid flows through the object,

the amount of heat loss of the heat-generating object is proportional to the flow rate of the fluid.

Specifically, the flowmeter sensor has two standard RTDs,

one for the heat source and one for measuring the temperature of the fluid.

When the fluid passes,

the temperature difference between the two is nonlinear with the flow rate.

The meter can convert this relationship into a linear output,

that measures the flow signal.

There are two design methods for the flowmeter manufactured,

by the principle of thermal diffusion:

one is based on the principle of constant temperature difference;

the other is based on the principle of constant power.

Based on a common data model:

P / ▷ T = A + B (Q) N.

Among them:

P—dissipated power,

▷T—the temperature difference between the two sensors,

Q—mass flow,

N—exponential coefficient,

A, B is the coefficient related to the thermal performance of the gas.

The principle of constant temperature difference:

▷T remains unchanged,

and the dissipated power P and the flow rate Q of the fluid are exponentially increasing.

Constant power principle:

The dissipated power is constant,

and the temperature difference ▷T is in a decreasing relationship with the flow rate Q of the fluid.

Know more about How Thermal Mass Flow Meter Technology Works?

Applications of Thermal Mass Flow Meter

The thermal measuring principle is widespread in the industry,

and is being used successfully in many applications with gas flow, for example:

  1. Compressed air (consumption, distribution)
  2. Carbon dioxide (for beverage production and chilling)
  3. Argon (in steel production)
  4. Nitrogen and oxygen (production)
  5. Natural gas (for burners and boiler feed control)
  6. Air and biogas measurement (e.g. in wastewater plants)

Advantages of Mass Flow Measurement

1 Thermal flowmeters have no moving parts,

which reduces maintenance and permits the use in demanding application areas, including saturated gas.

2 Gas mass meters calculate mass flow rather than volumetric flow,

and do not require temperature or pressure correction,

which means there is no additional expense,

for the purchase and installation of additional equipment.

3 Thermal flowmeters provide excellent accuracy,

and repeatability over a wide range of flow rates.

4 Thermal flow meters can measure flow in large pipes.

Thermal mass flowmeters

Our Engineer helps you to search for suitable measuring devices,

software or system components via product characteristics.

And leads you through an individual product selection via application parameters.

Manufacturer in China,

offer all types flow meters,

Like the:

magnetic flow meter, venturi flow meter,

turbine flow meter, vorter flow meter,

and More…….

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Please provide your measurement parameters or details. Sino-Instrument support customer customization and OEM

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